US police say a deadly car-to-car shooting and fiery crash at a major Las Vegas Strip intersection started with an argument in the valet area of the Aria resort.

Sheriff Doug Gillespie made the disclosure about the early morning incident that left three people dead and at least six injured.

Police were hunting a black Range Rover Sport that fled the scene at Las Vegas Boulevard and Flamingo Road.

The intersection is home to famous casinos including Bellagio, Caesars Palace and Bally's.

Authorities said at least one person in the Range Rover shot at a Maserati that then ran a red light and crashed into a taxi.

The taxi burst into flames, and the driver and passenger died. The driver of the Maserati also died, and his passenger was shot.

Police said they were contacting authorities in three neighbouring states about the Range Rover Sport with tinted windows and paper dealer ads in place of license plates that fled the scene about 4.30am (1.30am NZT).

In Southern California, the California Highway Patrol alerted officers in at least three counties to be on the lookout for the Range Rover with custom wheels, authorities said.

'LIKE DIE HARD'

Tourists staying in high-rise hotels around the scene found police tape blocking access to the area around the intersection.

Closures were expected to last most of the day, snarling traffic in the tourist corridor.

"This doesn't happen where we come from, not on this scale," said Mark Thompson, who was visiting from Manchester, England, with his wife.

"We get stabbings, and gang violence, but this is like something out of a movie. Like Die Hard or something."

Jeff Martin, 33, of Columbus, Ohio, said he was unable to cross the Strip several hours after the incident.

"When you're out at 4am nothing good's going to happen," he said.

Las Vegas Police Sergeant John Sheahan said the attack was not a rolling gun battle as previously described.

The cars were stopped at a light when at least one person in the Range Rover opened fire. Several people were inside the vehicle.

Six other vehicles were involved in the crash that followed, including the taxi and Maserati. The taxi was affiliated with Desert Cab company, according to general manager Sandy Shaver. He declined to comment further.

The taxi might have been propane-powered.

The incident marked the latest violence on the Strip since the beginning of the year. Two people were critically wounded in a shooting at a parking garage February 6, and a tourist was stabbed Saturday in an elevator at The Hotel at Mandalay Bay.

A spokesman for the Las Vegas Convention and Visitors Authority, Jeremy Handel, issued a statement reassuring people that much is being done to keep them safe.

"Recent incidents, while unfortunate, were isolated events," he said. "Las Vegas is among the safest travel destinations in the world and utilizes the most advanced technology and training to maintain a secure environment."

Las Vegas Police Officer Jose Hernandez acknowledged that the Strip has seen several violent incidents in recent weeks but said police have made arrests or identified suspects in each case.